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%I #17 Apr 07 2020 22:14:52
%S 11,83,271,641,1259,2161,3433,51217,7297,10007,13313,172829,21977,
%T 27449,33751,40961,49139,58321,68597,800011,926111,106487,1216711,
%U 138241,156253,1757617,196831,219523,2438911,270001,297911,327689
%N Smallest nontrivial extension of n-th cube which is a prime.
%C Extensions here cannot contain leading 0's, otherwise we would have a(8)=51203. - _Sean A. Irvine_, Apr 05 2020
%H Harvey P. Dale, <a href="/A030692/b030692.txt">Table of n, a(n) for n = 1..1000</a>
%t necp[n_]:=Module[{idn=IntegerDigits[n],k=1},While[!PrimeQ[ FromDigits[ Join[ idn, IntegerDigits[k]]]],k=k+2];FromDigits[Join[idn, IntegerDigits[ k]]]]; necp/@(Range[40]^3) (* _Harvey P. Dale_, Dec 11 2013 *)
%o (PARI) a(n) = {my(k=1); while(!isprime(x=eval(concat(Str(n^3), Str(k)))), k++); x;}; \\ _Michel Marcus_, Apr 07 2020
%Y Different from A029949.
%Y Cf. A030685 (for squares).
%K nonn,base
%O 1,1
%A _Patrick De Geest_
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